You can not do this with totalmix FX, apart from input channels and unless you route every Cubase channel/track to a different output in Cubase, which would limit you to a total of 30 tracks / channels inside Cubase.
Apart from that, totalmix FX also has a PFL AFL functionality, which as I also already said is good for example in standalone mode, but not really handy when working inside Cubase.